1. Field of the Invention
This invention relates to a plane die-cutting machine designed for die-cutting laminar material, for instance, even if not exclusively, paper material. This machine includes, in a known way a punch equipped with protruding blades and/or points and a counter-punch, as well as means to reciprocally move the punch and the counter-punch perpendicularly to the die-cutting plane, in order to allow for the introduction of a sheet of material to be die-cut, and subsequently to press in a controlled way this sheet between the punch and the counter-punch, so to obtain a penetration of the blades and/or points into the material under work as far as desired.
2. Description of the Prior Art
Plane die-cutting machines of this type are well known and used.
They practically consist of a plane press, one of the elements of which, the punch, bears a series of blades or points, the position and orientation of which may be changed at will, while the other element consists of a plane plate which, when actuated, presses the laminar material against the punch, as far as to reach a stop that defines the degree of penetration of die-cutting blades and/or points. These machines of known type, specially when designed to perform the die-cutting operation on sheets of important size and made of material having a certain resistance to blade and/or point penetration, substantially show the disadvantage of requiring high pressures and forces. In particular, once the die-cutting necessary specific pressure has been established, the machine should be capable of developing a total force equivalent to the specific pressure multiplied the surface of the material to be die-cut at each die-cutting cycle. This involves the need of creating moving masses, particularly the counter-punch and the pieces connected to it, which must be considerably sturdy, such as to support the forces involved, and therefore correspondingly heavy. So, besides the need of having means producing the desired total die-cutting force, it is necessary to have means determining the reciprocal movement of punch and counter-punch as far as to allow for the substitution of the sheet of material under work, these means being necessarily sized and operating in relation to the entity of the moving masses which, as it has been said, is considerable. Therefore, this involves the study of particularly powerful and onerous motor means and the need of reducing the speed of said approaching and departing reciprocal movements of punch and counterpunch, in relation to the weight of the moving masses and to the consequent inertia of same.